Teacher, is this sentence OK?
I spent $100 buying office supplies and attached is the receipt. Please reimburse me for that amount.
Bill, I believe the note is to an employer, not the to the place where the items were purchased.
I find it helpful to have the amount in the cover letter. Photocopies of receipts can be blurry, but the cover letter text will be clear. And there will be copies when reimbursements are needed.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
OK thanks. I misunderstood the context and in particular the term "reimbursement" vs. refund.